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How to make a teddy parachute. Number 2 in the series by Arthur Dibble (and the Ted Berets) November 2007 In conjunction with the web site www.tedberets.co.uk. WHAT ‘CHUTE.
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How to make a teddy parachute. Number 2 in the series by Arthur Dibble (and the Ted Berets) November 2007 In conjunction with the web site www.tedberets.co.uk
WHAT ‘CHUTE The following notes are based solely on my own experience gained over a number of years of bear bombing under the tight regulations of the BMISS and apply only to the "Sport" of dropping small, furry inanimate cuddlies (known as Para-fauna or Para-flora and more recently Para-fungi) from high altitudes lofted by a kite, or on windless days from any suitable high tower or building. Information and pictures from this presentation can be found on my web site. There are many different types of parachute in full size and with Teddy bears we try to simulate most of these. One of the added advantages in the small versions is that you can let your imagination run wild and make all sorts of shapes which will slow the decent of your bear.
WHAT ‘CHUTE • The first and most common type is the Hemispheric or mushroom 'chute which is easy to make and works well no matter how inaccurate your cutting and sewing. As they are so easy to make a large range of sizes can soon be produced for different weights of bear and varying wind speeds using the gore calculator we will look at later. Whilst decent rate is controlled mainly by overall area the central vent hole has a large effect. If no hole is left the 'chute will oscillate rapidly during decent.
WHAT ‘CHUTE • The type of 'chute used in human displays regularly seen at shows is the ram air type. These are very efficient and can be steered well. They are however very complex to make in the bear size and although they look fantastic when deployed I have found them problematic. Good plans are available in the Barker/Andrew publication The Big Book of Parachuting Teddies and I have seen these work superbly even in the Poulter/Swift scaled down versions. The new Swift RC version is awaited with baited breath.
WHAT ‘CHUTE • A relative newcomer to this end of the market is the Low Aspect Ratio Annular (LARA). I have designed this from some photos The BOF published. It is used by hang glider pilots, amongst others, as their reserve due to its small volume packed relative to its drag. The easiest way to describe it is as a ring doughnut cut in half cross ways.This still leaves a stabilising hole through the centre but the scooped air is trapped. Another major benefit is that the gore sections are such that the top and bottom are inverse of each other and can therefore be cut alternate ways up leaving no waste material. Plans are available on the web site suitable for fauna of about 6 oz in old money.
WHAT ‘CHUTE • A recent addition to my collection is the Fast Deploy 'Chute as tested by NATO over a French lake. I have had to draw this up from very vague photos so although the result looks good it is not that fast opening. Plans for this have been published in Kite Flier and are available on the web pages.
WHAT ‘CHUTE • We now come to the realms of fantasy that includes The carochute used for aerial bunnies, The Witches Hat by Doug Manners and Flora the air born sunflower from the house of Swift. • Others that come to mind are the spinning 'chute from Sky Bums, or a simple steamer which does slow the decent a little provided it is long enough and the fauna is light enough. The easiest of all to make if you are away from the necessities of life is a simple square of plastic with a string in each corner.(known as yes Johnny of course granddad can do that) • The final and most important one we use is the emperors clothes designed for Telly Tubbies, fluffy snakes, rats and especially annoying little sisters. • Free fall sky diving can be simulated by using very long rip cords but make sure the kite is high enough.(speak to Steve B about this defect) The same applies to bungee jumping but please use a dummy not a bear until you have got heights and weights correct.
MAKE STEP 1 • Having weighed your bear go to the gore calculator and try a few diameters to see how close you can get to the recommended weight. Next decide on the number of gores (sections) you wish to use. A guide is always 8 or more, an even number and the bigger the chute the more gores should be used. I start at 8 for a 0.5M diam, 12 for 0.75 and 16 minimum by the time I get to 1M. Now submit the program and print out the results.
MAKE STEP 2 • On a sheet of thin card mark the heights up the vertical edge then horizontally the half gore width. When this is completed draw a smooth line through all these points and cut out the half gore template. Again on the thin card draw a vertical line perpendicular to the bottom edge. Line the straight edge of the half gore template with this line and draw round it. Then turn it over, align the straight edge to the line and draw around it again. This should now give you a full gore template with both edges identical. If you are only going to make a few 'chutes you can continue with this card template but if you intend to do a number I would advise transferring it to a thin ply wood sheet.Mark the template with diameter and number of gores for future use.
MAKE STEP 3 • Choose the colour material you are going to use. It is best to use unproofed ripstop as it's porosity gives it a better flight and it deploys more readily than proofed. This can frequently be obtained from kite shops as rolls of standard ripstop are sometimes not proofed all the way to the end. However standard proofed ripstop works OK. Genuine parachute silk is excellent but is very difficult to work. Use some bright colours as these are easier to see if the ‘chute drifts a long way and make sure you use more than one colour as some show up better than others against differing backgrounds. Layout the material flat on your cutting board and put the template on top either vertically or horizontally along the weave. Keep all future parts in the same direction. Cut round the template using a hot cutter. (this saves having to do a double seam later). Turn the template over (this saves wear and tear) and top to bottom (this saves material) and cut out the next gore. Continue like this until all gores are cut.
MAKE STEP 4 • Lay 2 gore sections one on top of the other and starting at the thin end sew a seam 5mm from the edge Unfold these two pieces and lay gore 3 on top of gore 2 and sew the next hem. Continue this until all gores are sewn together to make a single sheet.
MAKE STEP 5 • Turn over the material so that the seams are on top and fold a 5mm hem along the top edge. This requires a little persuasion as the material changes width. Hem this edge.
MAKE STEP 6 • Now with all the pieces in-side-out lay the first section over the last and sew this seam to complete the hemisphere.The whole thing can now be turned right way out and the shape should be apparent. If you have not used a hot cutter the seams should be laid flat and a second line of stitching done along each one. Hot cutting is preferable as unproofed ripstop tends to fray on the second stitch line.
MAKE STEP 7 • At this point the shroud lines must be prepared. They should be about 1.5 X the gore length and the same number as gores except for the LARA where extras are required for the centre lines. I use a braided polyester line of about 20kg test on all 'chutes no mater what size as any thing smaller tends to get tangled very badly.
MAKE STEP 8 • Back to the sewing machine and starting half way round any gore on the main circumference make a single hem 5mm wide. Each time you get to a seam, double over the end of a shroud line and tuck it inside the hem as you sew over it. This should fix the shroud line in place. Continue around the seam until all shrouds are fitted.
MAKE STEP 9 • When you get back to where you started fold the seam over a second time and lay the shroud lines outwards. Using a tight multi stitch zigzag go right round the hem until you return to the start point.
MAKE STEP 10 • Gather the shroud lines into a bundle ensuring that the points where they attach to the canopy are together and cut the lines to the same length. Separate them into two bundles divided uniformly across two halves of the canopy. Attach these two bundles to the lead lines from the back pack or harness.
MAKE 11 • If you do not intend to use a full back pack system a suspension point must be fitted. The simplest way to do this is to sew a loop across the top vent hole and fit a split ring.
Now you should have a completed parachute. Attach to unsuspecting soft object. Take to high altitude and release.
THAT’S ALL FOLKS MOST OF ALL GET OUT THERE AND HAVE AS MUCH FUN AS I HAVE HAD FOR SO MANY YEARS. www.tedberets.co.uk
If you want to see more Please come to WHKF Kite Festival in May At A location near Swindon www.whkf.org.uk
OTHER PRESENTATIONS BY ARTHUR DIBBLE 1. HOW TO PARACHUTE A TEDDY • HOW TO MAKE A TEDDY PARACHUTE BACK PACK. • HOW TO MAKE THE WHKF SLED KIT • AN INTRODUCTION TO KITES (a brief outline of what kites are about) 5. KITES AND TRANSPORT (a picture history of kite powered vehicles)